Gain: Increasing the gain control boosts overall output and adds Germanium character and distortion/fuzz to the tone. Fully counter-clockwise is minimum setting, fully clockwise is max gain.

Mid-Shift: Extends the upper mids/treble range of the signal when switched to the right. This control is only effective when the treble knob is set to a non-zero position.

Gain Shift: Extends the bass frequencies of the signal when switched to the right. This control is only effective when the gain knob is turned up past the minimum setting. The bass frequencies have a tighter feel when switched to the left and a looser feel when switched to the right.